package org.example.domain.strategy.service.armory;

import lombok.extern.slf4j.Slf4j;
import org.example.domain.strategy.model.entity.StrategyAwardEntity;
import org.example.domain.strategy.model.entity.StrategyEntity;
import org.example.domain.strategy.model.entity.StrategyRuleEntity;
import org.example.domain.strategy.repository.IStrategyRepository;
import org.example.types.common.Constants;
import org.example.types.enums.ResponseCode;
import org.example.types.exception.AppException;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.math.BigDecimal;
import java.math.RoundingMode;
import java.security.SecureRandom;
import java.util.*;

/**
 * @author Fuzhengwei bugstack.cn @小傅哥
 * @description 策略装配库(兵工厂)，负责初始化策略计算
 * @create 2023-12-23 09:44
 */

@Slf4j
@Service
public class StrategyArmoryDispatch implements IStrategyArmory,IStrategyDispatch{

    @Resource
    IStrategyRepository  repository;

    @Override
    public boolean assembleLotteryStrategy(Long strategyId) {
        //1.查询策略配置
        List<StrategyAwardEntity> strategyAwardEntities = repository.queryStrategyAwardList(strategyId);

        //2.缓存奖品库存【用于decr扣减库存使用】
        for(StrategyAwardEntity strategyAward :strategyAwardEntities){
            Integer awardId = strategyAward.getAwardId();
            Integer awardCount = strategyAward.getAwardCount();
            cacheStrategyAwardCount(strategyId, awardId, awardCount);


        }


        //3.1默认装配配置【全量抽奖概率】
        assembleLotteryStrategy(String.valueOf(strategyId),strategyAwardEntities);

       //3.2.权重策略配置-适用余额rule_weight 权重规则配置
        StrategyEntity strategyEntity = repository.queryStrategyEntityByStrategyId(strategyId);
        String ruleWeight = strategyEntity.getRuleWeight();
        if(null==ruleWeight) return true;


        StrategyRuleEntity strategyRuleEntity=repository.queryStrategyRule(strategyId,ruleWeight);
        if(null==strategyRuleEntity){
            throw  new AppException(ResponseCode.STRATEGY_RULE_WEIGHT_IS_NULL.getCode(), ResponseCode.STRATEGY_RULE_WEIGHT_IS_NULL.getInfo());
        }

        Map<String, List<Integer>> ruleWeightValueMap = strategyRuleEntity.getRuleWeightValues();
        Set<String> keys = ruleWeightValueMap.keySet();
        for(String  key:keys){
            List<Integer> ruleWeightValues = ruleWeightValueMap.get(key);
            ArrayList<StrategyAwardEntity> strategyAwardEntitiesClone = new ArrayList<>(strategyAwardEntities);
           strategyAwardEntitiesClone.removeIf(entity->!ruleWeightValues.contains(entity.getAwardId()));

           assembleLotteryStrategy(String.valueOf(strategyId).concat("_").concat(key),strategyAwardEntitiesClone);



        }


        return true;
    }

    @Override
    public boolean assembleLotteryStrategyByActivityId(Long activityId) {
        Long strategyId = repository.queryStrategyIdByActivityId(activityId);
        return assembleLotteryStrategy(strategyId);

    }


    private  void  assembleLotteryStrategy(String key,List<StrategyAwardEntity> strategyAwardEntities){
        //1.获取最小概率值
        BigDecimal minAwardRate= strategyAwardEntities.stream()
                .map(StrategyAwardEntity::getAwardRate)
                .min(BigDecimal::compareTo)
                .orElse(BigDecimal.ZERO);


        //2.获取概率值总和
        BigDecimal totalAwardRate= strategyAwardEntities.stream()
                .map(StrategyAwardEntity::getAwardRate)
                .reduce(BigDecimal.ZERO,BigDecimal::add);


        //3.用1%0.0001获取概率范围，百分位，千分位，万分位
        BigDecimal rateRange= totalAwardRate.divide(minAwardRate, 0, RoundingMode.CEILING);


        //4.生成策略奖品概率查找表 ，这里指需要再list集合中，存放上对应的奖品占位即可，占位越多等于概率越高
        ArrayList<Integer>  strategyAwardSearchRateTables= new ArrayList<>(rateRange.intValue());
        for (StrategyAwardEntity strategyAward : strategyAwardEntities) {
            Integer awardId = strategyAward.getAwardId();
            BigDecimal awardRate = strategyAward.getAwardRate();
            //计算出每个概率值需要存放到查找表的数量，循环填充
            for (int i = 0; i < rateRange.multiply(awardRate).setScale(0, RoundingMode.CEILING).intValue(); i++) {
                strategyAwardSearchRateTables.add(awardId);
            }

        }


        //5.对存储的奖品进行乱序操作
        Collections.shuffle(strategyAwardSearchRateTables);


        //6.乱序map表
        HashMap<Integer, Integer> shuffleStrategyAwardSearchRateTables = new HashMap<>();
        for(int i=0;i<strategyAwardSearchRateTables.size();i++){
            shuffleStrategyAwardSearchRateTables.put(i,strategyAwardSearchRateTables.get(i));
        }

        //8.存储到redis
        repository.storeStrategyAwaraSearchRateTables(key,shuffleStrategyAwardSearchRateTables.size(),shuffleStrategyAwardSearchRateTables);
    }


    /**
     * 缓存奖品库存到Redis
     *
     * @param strategyId 策略ID
     * @param awardId    奖品ID
     * @param awardCount 奖品库存
     */
    private void cacheStrategyAwardCount(Long strategyId, Integer awardId, Integer awardCount) {
        String cacheKey = Constants.RedisKey.STRATEGY_AWARD_COUNT_KEY + strategyId + Constants.UNDERLINE + awardId;
        repository.cacheStrategyAwardCount(cacheKey, awardCount);
    }



    @Override
    public Integer getRandomAwardId(Long strategyId) {
         //分布式部署下 不一定为当前应用做的策略装配。也就是值不一定会保存到本应用，而是分布式应用，所以需要从Redis中获取
        int rateRange = repository.getRateRange(strategyId);
         // 通过生成的随机值 获取概率值奖品查找表的结果
        return repository.getStrategyAwardAssemble(String.valueOf(strategyId),new SecureRandom().nextInt(rateRange));
    }

    @Override
    public Integer getRandomAwardId(Long strategyId, String ruleWeightVlue) {
        String key = String.valueOf(strategyId).concat("_").concat(ruleWeightVlue);

        //分布式部署下 不一定为当前应用做的策略装配。也就是值不一定会保存到本应用，而是分布式应用，所以需要从Redis中获取
        int rateRange = repository.getRateRange(key);
        // 通过生成的随机值 获取概率值奖品查找表的结果
        return repository.getStrategyAwardAssemble(key,new SecureRandom().nextInt(rateRange));
    }

    @Override
    public Boolean subtractionAwardStock(Long strategyId, Integer awardId,Date endDateTime) {
        String cacheKey = Constants.RedisKey.STRATEGY_AWARD_COUNT_KEY + strategyId + Constants.UNDERLINE + awardId;


        return repository.subtractionAwardStock(cacheKey);
    }
}